The present invention relates generally to video systems, and in one exemplary application to multi-image video systems.
Existing closed circuit television (“CCTV”) analog video transmission-based surveillance installations typically employ ITU/ISO NTSC (720×480) or PAL (720×576) standard video resolutions that are limited by realizable system bandwidth and cost constraints associated with such installations. FIG. 1 depicts an example of such a prior art CCTV installation 100 including a standard resolution (i.e., NTSC or PAL) digital camera 102 that is connected to a multi-port personal computer-based digital video recorder (“DVR”) 104 through a bandwidth-limited analog transmission interface 106 to provide a standard resolution displayed image 108.
Factors that limit the maximum bandwidth of such prior art installations include signal attenuation associated with required maximum installation cabling length (typically up to 1000 feet), the type of cabling used (typically standard RG59 coax) and standard installation techniques that can result in non-optimal terminations. Increased costs associated with use of improved cabling, improved installation techniques, and/or custom interface circuitry preclude their use to achieve increased bandwidth capability in many situations. Transmission of higher resolution video imagery may be accomplished using digital transmission technology, but requires additional investments for new higher cost equipment, including compression and transport circuitry.